From nobody Wed Dec 10 13:44:25 2025 X-Original-To: net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4dRH552xRvz6Kb3N for ; Wed, 10 Dec 2025 13:44:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R12" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4dRH551DLxz45ht for ; Wed, 10 Dec 2025 13:44:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1765374265; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1g15vLv+E10YSBTI7nthS0ieBAU7d6mhYVQYD1emMI0=; b=d5yYma21XDwcgXk/G0k1Q5Vs32vlV7O+SbZ1W3hb3iPn+tRhq73VTgpLkxUtvBjRSwiWGk vxrp9lEKGNKOjIiHJHI1/0sm0TtTzs5/AWfHBD9DmUmWfPgG52kFZ3r9DmOeZCFXhb1Swu UEBSb00++pfONwkLbxrjnNRT3fq5KO6O3q+fyi7ZGCsWZ7nlL4BTrzLLCoLtokK/R0RuXi s6sQnsl8vU3AMdnibv8vgICgs9duW3kyoer2Gmtj+sLM9kbr7wBYJOptnD9KmRScu3Z97+ pcOa9CKEoiWB3BR3wbPFg1eTFAAiDv1J+WfMDKrwthfj0rB6jJfFax4xhWnUMg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1765374265; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=1g15vLv+E10YSBTI7nthS0ieBAU7d6mhYVQYD1emMI0=; b=GJWjfSAeGhoSms5WLipuujUzgPKwKCECo3O1KA+2z5vBI0wgzVz4mYHdvEbGZ3ZPYWRrvd lYVQLDB+BuXc7c8Km4tpkRypByaKXzEKcx5ardVlXKzAzcqH1OWw7YpARYAsE41MhcwL31 ADFQWQ/DVi5wxw9NWqO4oNKvHkxjacomjeCzF7JiREKE/Vl8SYBPB6p0gw+xn9HMkLL1/u Fk+INqyA2uPCO6qTWVFZLJIvTBo+RVmui44wjdFTJW8+CPITHKTU3GtkTi2Isv+bSu3j+6 OijeEE8apAokAproGQdgvKEyUP3KxIbDgKswZe1dtJ5iI0TrNw7W01QQNTp0iw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1765374265; a=rsa-sha256; cv=none; b=IV0cotNi3+1og0W30aBT6BjjkaMLaMsKdOZyoDRYrEraj3+QUSPF5R838/51xyMlyb24UH fTqY/K3R2tXxGicmg3ck4lKBZohzYhstKS7vRZTeo7j0Ec5Yo+bojRAgoPAAUp+v+Iz6ZK 5g04w7XVNaTU2Vh04Ht68wnaLWTmJvEoNLDuTVJYjdnk/bgS8ta6+GJiknkj7EGLUpqLbt fD4dZjf1pQ+XY2IBZAEhlgyxSmK5crgjbP/bNohBlmetb/x9mOFzlzwf6NHYheCO7C8KvY +8XhssKjv3cMFj2VlrJH+RzDHYog0LrOatqWb7iXLHQsPGF8dFervu8N2CHGvA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4dRH550dZczn4T for ; Wed, 10 Dec 2025 13:44:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 5BADiORp011509 for ; Wed, 10 Dec 2025 13:44:24 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 5BADiOVA011508 for net@FreeBSD.org; Wed, 10 Dec 2025 13:44:24 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: net@FreeBSD.org Subject: [Bug 291420] [epair] Bad UDP packet checksum with epair(4) and txcsum enabled Date: Wed, 10 Dec 2025 13:44:25 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 14.3-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: tuexen@freebsd.org X-Bugzilla-Status: In Progress X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: tuexen@freebsd.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@FreeBSD.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D291420 --- Comment #19 from Michael Tuexen --- (In reply to vova from comment #17) The kernel will take care. The problem here is that bge interfaces announce TXCSUM support, but only do this for TCP. All other interfaces I know of, support no checksum offloadin= g at all, TCP and UDP, or SCTP, TCP and UDP. Only TCP is what breaks here UDP traffic. Setting forced_udpcsum to 1, adds support for UDP checksum offloading. Unfortunately, the hardware implementa= tion does not handle the case where the computation gives 0 correctly. That is w= hy the default is off. Disabling TXCSUM also avoids being hit by the problem, since then no checksum offloading at all is done. The long term solution will most likely be to add the capability to the bri= dge interface to compute the checksum in software when needed. The short term solution might be just to disable TXCSUM per default for epair... --=20 You are receiving this mail because: You are on the CC list for the bug.=